The open-bridge construction of the BL 8x44 HD enables a secure one-handed operation and ensures high freedom of movement with the lightweight construction that is specific to BL binoculars. These lightweight binoculars weighing 740 grams have a firm grip and are waterproof to a depth of five metres. Nitrogen gas purging prevents the glass surfaces from fogging even during strong temperature changes. The powerful optical systems consist of multi-coated lenses.